Patent · US Expired

Heat shrinkable multilayer packaging film of blended copolymers and elastomers

US4196240A · kind A · utility

34Cited by
5References
22Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 18, 1978
Grant dateApr 1, 1980
Priority date
Expiry dateJan 18, 1998

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T428/31928
  • WIPO fieldSurface technology, coating
  • WIPO sectorChemistry

Abstract

A heat-shrinkable multilayer film suitable for use in the packaging of a frozen poultry, includes a first outer layer comprising a blend of propylene-ethylene copolymer having a high isotactic molecular structure with less than about 6% by weight being ethylene and having a melt flow of from about 1.5 to about 18 decigrams per minute; a (butene-1)-ethylene copolymer having a high isotactic molecular structure with less than about 10% by weight ethylene and having a melt flow of from about 0.1 to about 5.0 decigrams per minute, and a thermoplastic elastomer selected from the group consisting of ethylene-propylene copolymers and ethylene-propylene diene terpolymers, the ratio by weight of the propylene-ethylene copolymer to the (butene-1)-ethylene copolymer being from about 2:1 to about 1:2 and the thermoplastic elastomer being present from about 10% to about 50% by weight, and a second outer layer comprising an ethylene-(butene-1) copolymer having a melt flow of from about 0.1 to about 1.0 decigram per minute, having a density of from about 0.916 to about 0.920 gram per cubic centimeter, and being a linear polymer; the multilayer film being biaxially oriented.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.